Motivation:
Commit c32c520edd incorrectly skip the bytes of the replay decoder buffer. The number of bytes to skip is determined by ByteBuf#readableBytes() instead of using ByteToMessageDecoder#actualReadableBytes(). As result it throws an exception because the ByteBuf provided will return a too large value (Integer.MAX_VALUE - reader index) causing a bound check error in the skipBytes method. This is not detected by the tests because most tests are calling the decode(...) method with a regular ByteBuf. In practice when this method is called with a specialized ByteBuf when channelRead(...) is called. Such tests should actually use channelRead with proper mocking of the ChannelHandlerContext
Modification:
- Rewrite the MqttCodecTest to use channelRead(...) instead of decode(...) and use proper mocking of ChannelHandlerContext to get the message emitted by the decoder.
- Use actualReadableBytes() instead of buff.readableBytes() to compute the number of bytes to skip
Result:
Skip correctly the number of bytes when a too large message is found and improve testing. See #11361
Signed-off-by: Julien Viet <julien@julienviet.com>
06f7deb030